In which truth is a defense

One might say that the Tarek ibn Ziyad Academy K-8 charter school in suburban St. Paul is an Islamic school in all but name, except that that even its name is Islamic. Among other things, the school’s principal is an imam and almost all of its students are Muslim. It is housed in a building was owned originally by the Muslim American Society of Minnesota (I’m not sure who owns it now). The school has in any event had a mutually beneficial relationship with MAS Minnesota since the school’s inception. The study of Arabic is required at the school. The Arabic comes in handy for the religious studies that follow the regular school day.
The ACLU of Minnesota has brought a lawsuit challenging the legality of the school’s operation on public funds in federal district court in Minnesota. Discussing the lawsuit, ACLU Minnesota executive director Chuck Samuelson observed: “The issue with TiZA, frankly, was the incredible commingling of church and state. It’s a theocratic school. It is as plain as the substantial nose on my face.”
TiZA now alleges that Samuelson and the ACLU Minnesota have defamed it, asserting several counterclaims against the ACLU Minnesota for amounts in excess of $100,000 (i.e., an unlimited amount). The Star Tribune reports on the gist of TiZA’s claims:

The ACLU’s lawsuit and statements led to threats against the school’s staff, and the lawsuit and resulting negative attention hurt the school’s learning environment and caused several students to withdraw from the school, TiZA said in a statement Tuesday. At least 10 prospective TiZA teachers withdrew their applications in the middle of the hiring process, leaving the school with several open positions, the statement said.

The ACLU Minnesota’s lawsuit against TiZA is predicated on the establishment clause of the First Amendment as interpreted by the Supreme Court. I’m pretty sure there is another clause of the First Amendment that applies to TiZA’s claims against the ACLU Minnesota, but even the common law of defamation provides that truth is a defense.